This moves us towards variable length effect keys. The overall program key now allows for it. After the header it stores an array of offsets to effect keys. This allows us to grab the effect keys to pass to effects when they generate code. It also ensures that we can't get a collision by sets of keys that are different lengths but are the same when appended together.

R=robertphillips@google.com, jvanverth@google.com, egdaniel@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/356513003

1 files changed, 26 insertions, 23 deletions

diff --git a/include/gpu/GrBackendEffectFactory.h b/include/gpu/GrBackendEffectFactory.h
index af8d5c76c5..32f14f2746 100644
--- a/include/gpu/GrBackendEffectFactory.h
+++ b/include/gpu/GrBackendEffectFactory.h
@@ -12,6 +12,7 @@
 #include "SkTemplates.h"
 #include "SkThread.h"
 #include "SkTypes.h"
+#include "SkTArray.h"
 
 /** Given a GrEffect of a particular type, creates the corresponding graphics-backend-specific
     effect object. Also tracks equivalence of shaders generated via a key. Each factory instance
@@ -27,23 +28,32 @@ class GrGLEffect;
 class GrGLCaps;
 class GrDrawEffect;
 
+/**
+ * Used by effects to build their keys. It incorpates each per-effect key into a larger shader key.
+ */
+class GrEffectKeyBuilder {
+public:
+    GrEffectKeyBuilder(SkTArray<unsigned char, true>* data) : fData(data), fCount(0) {
+        SkASSERT(0 == fData->count() % sizeof(uint32_t));
+    }
+
+    void add32(uint32_t v) {
+        ++fCount;
+        fData->push_back_n(4, reinterpret_cast<uint8_t*>(&v));
+    }
+
+    size_t size() const { return sizeof(uint32_t) * fCount; }
+
+private:
+    SkTArray<uint8_t, true>* fData; // unowned ptr to the larger key.
+    int fCount;                     // number of uint32_ts added to fData by the effect.
+};
+
 class GrBackendEffectFactory : SkNoncopyable {
 public:
     typedef uint32_t EffectKey;
-    enum {
-        kNoEffectKey = 0,
-        kEffectKeyBits = 10,
-        /**
-         * The framework automatically includes coord transforms and texture accesses in their
-         * effect's EffectKey, so effects don't need to account for them in GenKey().
-         */
-        kTextureKeyBits = 4,
-        kTransformKeyBits = 6,
-        kAttribKeyBits = 6,
-        kClassIDBits = 6
-    };
 
-    virtual EffectKey glEffectKey(const GrDrawEffect&, const GrGLCaps&) const = 0;
+    virtual bool getGLEffectKey(const GrDrawEffect&, const GrGLCaps&, GrEffectKeyBuilder*) const = 0;
     virtual GrGLEffect* createGLInstance(const GrDrawEffect&) const = 0;
 
     bool operator ==(const GrBackendEffectFactory& b) const {
@@ -55,10 +65,6 @@ public:
 
     virtual const char* name() const = 0;
 
-    static EffectKey GetTransformKey(EffectKey key) {
-        return key >> (kEffectKeyBits + kTextureKeyBits) & ((1U << kTransformKeyBits) - 1);
-    }
-
 protected:
     enum {
         kIllegalEffectClassID = 0,
@@ -69,18 +75,15 @@ protected:
     }
     virtual ~GrBackendEffectFactory() {}
 
-    static EffectKey GenID() {
-        SkDEBUGCODE(static const int32_t kClassIDBits = 8 * sizeof(EffectKey) -
-                           kTextureKeyBits - kEffectKeyBits - kAttribKeyBits);
+    static int32_t GenID() {
         // fCurrEffectClassID has been initialized to kIllegalEffectClassID. The
         // atomic inc returns the old value not the incremented value. So we add
         // 1 to the returned value.
         int32_t id = sk_atomic_inc(&fCurrEffectClassID) + 1;
-        SkASSERT(id < (1 << kClassIDBits));
-        return static_cast<EffectKey>(id);
+        return id;
     }
 
-    EffectKey fEffectClassID;
+    int32_t fEffectClassID;
 
 private:
     static int32_t fCurrEffectClassID;